applicationpractical
Why does a plastic container turn white when you bend it?
When you bend certain plastics, you are physically pulling and forcing the tangled polymer chains to align in one direction. This force causes tiny crystalline zones to slide past one another and creates micro-voids that scatter light. This scattering makes the stressed area look cloudy or white, warning you that the chains are reaching their breaking point.
Action
Take a plastic milk jug or yogurt lid and bend it back and forth. Watch the crease turn white as the internal polymer structure deforms and reorganizes.
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